Urban Subsidence Monitoring Research Articles

Spatial and temporal characteristics analysis for land subsidence in Shanghai coastal reclamation area using PS-InSAR method

In recent decades, large-scale reclamation projects have been performed in the intertidal flat area of Shanghai, China. Due to the self-weight consolidation of the foundation and dynamic load caused by human activities, the newly reclamation area will sink within a period of time after the land is formed. Therefore, it is necessary to carry out surface deformation monitoring for taking preventive measures in advance. In this research, the PS-InSAR technology, mostly used for urban subsidence monitoring, was applied to obtain the ground deformation information of Shanghai coastal area based on ENVISAT/ASAR (2007.07-2010.02) and Sentinel-1A (2017.07-2020.02) datasets. The results showed that: 1) Compared with ASAR data, the Sentinel-1A data could distinguish more coherent points and get more comprehensive deformation distribution characteristics. 2) Most high-coherent points were detected in artificial objects, especially airport runways, buildings, roads and seawalls. 3) There was obvious uneven land subsidence in the study area during the two monitoring periods, the PS points with high subsidence rates (<-20 mm/a) mainly distributed around Dishui Lake and artificial seawalls. 4) The ground subsidence velocity of the newly formed land gradually slowed down over times, with the average subsidence rate decreased from -10.45 mm/a to -4.94 mm/a. Our study proved that remote sensing monitoring for ground subsidence in reclaimed land could be realized based on PS-InSAR technology, which could provide the spatial distribution characteristics of subsidence in large-scale and long-term series and help the sustainable development of coastal engineering construction.

基于层次分析法的城市沉降监测方案优选

基于层次分析法的城市沉降监测方案优选

Urban subsidence monitoring by SBAS-InSAR technique with multi-platform SAR images: a case study of Beijing Plain, China

ABSTRACT Beijing, as the capital of China, suffers severe subsidence caused by groundwater withdrawal. In this paper, the SBAS-InSAR technique was used to detect surface deformations in the Beijing plain. 47 scenes Envisat ASAR images obtained during June 2003 to August 2010, and 24 Radarsat-2 images obtained during November 2010 to December 2013 were employed to retrieve vertical deformation characteristic over this area. The deformation magnitude, evolution process and spatial distribution of representative targets that occurred during 11 years were retrieved. The vertical surface displacement rates during two periods were validated via leveling observations, which have an RMSE =1.15mm/a, which indicates that the two types of subsidence matched very well. The interferometric results revealed that the subsidence during the two periods show similar special distributions and have an uneven spatial-temporal trend. The scope and deformation rates of funnels continuously increased with from 2003 to 2013. Meanwhile, multiple expressways and urban ring roads spanned the subsidence funnel with sharp deformation rate, and showed different subsidence properties along their paths. Additionally, the spatial and temporal correlation analyses between the deformation measurements and the dynamic variation of groundwater pumping was also performed to explore the response relationship.

MEASURING SURFACE SUBSIDENCE IN WUHAN, CHINA WITH SENTINEL-1 DATA USING PSINSAR

Abstract. We use the potential of Sentinel-1 for urban subsidence monitoring. A case study was conducted in Wuhan using Sentinel-1A images acquired from 22nd June 2015 to the 24th of April 2017 acquired from an ascending orbit. Our results using PSInSAR are compared to a recent study using SBAS. Moreover, in another experiment, only more recent data, containing 18 images from the 7th of March 2017 to the 14th of March 2018, have been processed in order to analysis changes in the subsidence behavior over the study area. In addition to that, the proposed method (PSInSAR) was used to measure the water height in the east lake using metallic objects as stable PS points.

Persistent Scatterers Interferometry Technique for Urban Subsidence Monitoring in Kazakhstan Republic

Abstract Methods of SAR interferometry data processing can detect and monitor low-amplitude motion of the earth's surface having the natural or man-made nature. The method of Persistent Scatterers Interferometry (PSI) successfully used for monitoring above mentioned processes in many cities around the world. The results of PSI technologies allow to providing geodynamic zoning of urban areas and identifying the objects exposed to linear deformation - separate objects, extended linear features (e.g. subway). The paper present the results of PSI COSMO-SkyMed data processing for Astana city (capital of Kazakhstan), including the displacement distribution for individual buildings and structures, and areal coverage analysis of surface movements. Data of ENVISAT ASAR images for Almaty city received from ESA grant C1.P15390 “Spatio-temporal analysis of surface displacements in urban areas with high seismic risk by SAR interferometry data”.

Ground-Based Polarimetric SAR Interferometry for the Monitoring of Terrain Displacement Phenomena–Part II: Applications

Urban subsidence and landslides are among the greatest hazards for people and infrastructure safety and they require an especial attention to reduce their associated risks. In this framework, ground-based synthetic aperture radar (SAR) interferometry (GB-InSAR) represents a cost-effective solution for the precise monitoring of displacements. This work presents the application of GB-InSAR techniques, particularly with the RiskSAR sensor and its processing chain developed by the Remote Sensing Laboratory (RSLab) of the Universitat Politècnica de Catalunya (UPC), for the monitoring of two different types of ground displacement. An example of urban subsidence monitoring over the village of Sallent, northeastern of Spain, and an example of landslide monitoring in El Forn de Canillo, located in the Andorran Pyrenees, are presented. In this framework, the key processing particularities for each case are deeply analyzed and discussed. The linear displacement maps and time series for both scenarios are showed and compared with in-field data. For the study, fully polarimetric data acquired at X-band with a zero-baseline configuration are employed in both scenarios. The displacement results obtained demonstrate the capabilities of GB-SAR sensors for the precise monitoring of ground displacement phenomena.

Monitoring of urban subsidence with SAR interferometric point target analysis: A case study in Suzhou, China

Ground subsidence, mainly caused by over exploitation of groundwater and other underground resources, such as oil, gas and coal, occurs in many cities in China. The annual direct loss associated with subsidence across the country is estimated to exceed 100 million US dollar. Interferometric SAR (InSAR) is a powerful tool to map ground deformation at an unprecedented level of spatial detail. It has been widely used to investigate the deformation resulting from earthquakes, volcanoes and subsidence. Repeat-pass InSAR, however, may fail due to impacts of spatial decorrelation, temporal decorrelation and heterogeneous refractivity of atmosphere. In urban areas, a large amount of natural stable radar reflectors exists, such as buildings and engineering structures, at which radar signals can remain coherent during a long time interval. Interferometric point target analysis (IPTA) technique, also known as persistent scatterers (PS) InSAR is based on these reflectors. It overcomes the shortfalls in conventional InSAR. This paper presents a procedure for urban subsidence monitoring with IPTA. Calculation of linear deformation rate and height residual, and the non-linear deformation estimate, respectively, are discussed in detail. Especially, the former is highlighted by a novel and easily implemented 2-dimensional spatial search algorithm. Practically useful solutions that can significantly improve the robustness of IPTA, are recommended. Finally, the proposed procedure is applied to mapping the ground subsidence in Suzhou city, Jiangsu province, China. Thirty-four ERS-1/2 SAR scenes are analyzed, and the deformation information over 38,881 point targets between 1992 and 2000 are generated. The IPTA-derived deformation estimates correspond well with leveling measurements, demonstrating the potential of the proposed subsidence monitoring procedure based on IPTA technique. Two shortcomings of the IPTA-based procedure, e.g., the requirement of large number of SAR images and assumed linear plus non-linear deformation model, are discussed as the topics of further research.

Analysis of subsidence using TerraSAR-X data: Murcia case study

This paper presents an analysis of the performance of the Coherent Pixel Technique for urban subsidence monitoring using TerraSAR-X data. Repeated observations for the period comprised between July 2008 and September 2009 have been used. For this purpose the city of Murcia has been selected as a test-site because it is affected by subsidence due to groundwater exploitation. The obtained results are compared with those obtained from ERS/ENVISAT data belonging to the same period and validated with pre-existing information. Subsidence data reveal average rates of subsidence for the whole area up to − 5 mm/year with local values that reach − 35 mm/year. These results are analyzed with respect to the main factors that control subsidence mechanisms: the thickness of the compressible layer, the presence of pumping wells, and the water table variation. Finally a local analysis of several buildings and infrastructures is presented. Therefore the usefulness of X-band radar technology, not only to improve the knowledge of this kind of regional phenomenon, but also to study its effects on local areas such as buildings and infrastructures is demonstrated.

Long term monitoring of urban subsidence by Permanent Scatterer DInSAR

Abstract A new dragonfly of family Meganeuridae Shenzhousia qilianshanensis ge. et sp. nov., discovered from Ningxia Hui Autonomous Region in North China, is described in the present paper. It has an estimated wingspan of about 450–500 mm and may be the largest fossil insect in Late Carboniferous Namurian Stage discovered by far. The new species is referred to Meganeuridae because of the presence of the characteristic oblique vein between anterior branch of radius (RA) and posterior branch of radius (RP) near the base of RP2. It differs from other genera within the family in the following characteristics: Precostal area short and not extending to the midwing; posterior branch of subcostal vein short, merging into costal vein near the level of originating point of IR2; RP forking earlier than anterior branch of media basally; RP1+2 and RP3+4 parallel and close to each other for a long distance, and then diverge gradually surpass midwing. * Supported by National Natural Science Foundation of China (Grant No...